Finely-divided-fuel-burning furnace



Oct. v

H. KREISINGER FINELY DIVIDED' FUEL BURNING mamen' 2 Sheets-Sheet 1 Filed Sept. 26. '1924 fills IN VEN TOR B Y I *MWL A TTORNE Y Patented Oct. 18, 19.27.

UNITED STATES 1,645,651 PATENT OFFICE.

HENRY KREIS'INGER, OF PIERMONT, NEW YORK, .A'SSIGNOR TO COMBUSTION ENGI- NEERING CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

Original application filed December 13, 1920, Serial No. 439,224. 'Divided and this application fled September 26, 1924. 'Serial No. 740,015.

T his invention relates to furnaces such as are used for the burning of fuel in finely divided form, as for example inthe form of pulver-ized coal, under stationary boilers. I

One of the primary objects of my invention is to deliver' pre-heated air for combustion into the combustion chamber so t-o increase the eliiciency of the installation,

while at. the same time the refractory structure is to be cooled bythe pre-heating of the combustion air, i. e. by the absorption of the heat from theirefractory structure by combastion air traversing thesame before entry into the combustion space.A

More specilically my invention is directed to a novel form` of channelled wall construction by virtue of which the combustion air is heated to a higher degree, and the walls cooled in such manner as to avoidv contraction and expansion difliculties.

rl`his ,application is division .of my eo` vpending application, Serial No.l 430,224,

` nace embodying the invention;

filed on Dec. 13th, 192.0," issued as Patent No. 1,510,994, October 7th, 1924.

Now the foregoing, together with such other objects and advantages as may hereinafter appeal', or are incident to my invention, are realized, is illustrated in preferred form in the accompanying drawings wherein Fig. 1 is a vertical section through a fur- F 2 isa front elevation; and

Fig. 3 .1s a sect1on taken on the lme 3 3 of Fig. 2. Y

Referring now to the drawings the reference character A indicates the furnace or combustion chamber, having anoutlet 7 in the upper part thereof', over which is located the boiler 8. Fuel is admitted in powdered form into the upper part of the combustion chamber adjacent the front wall 9 and in a downward direction, through the top or arch 9 through one or more burners 9l1 there preferably being a plurality of these burners arranged in a rW. The fuel is admitted with carrying air and additional air is induced through the burner casing, in a manner now Well understood-in this art. The. fuel and flame stream takes a U-shape course through the 'combustion space, combustion being completed before the tubes of the boiler 8 are reached. Only a portion of the tot-al air required for combustion is supplied With the coal and through the burner, the balance of the air required for combusderstood thatthe compartment 14 has inlets tion being supplied to the combustion space at successive leve-ls, as will be set forth.

The efliciency of the furnace will be greatly increased if a large part of the air for combustion is pre-heated. In the enibodiments shown, this is brought about by providing three vertically spaced, horizontally extending channels or conipartmentf 13, 14 and 15 within the walls 9, 10, 11 and 12. The channel 13 begins atthe-left hand sde of Fig. 3 and runs through the side wall 11,-the vrear wall 10, the side wally 12 and then through the front wall 9, tern'iinating short of the side wall 11. Air flows through the inlet 1G under control of the damper 17 through the channel. 13 in the direction of the arrows, and such air in traversing the side wall 11, the rear wall 10, the side wall l2 and the front wall 9 becomes very highly heated indeed before it is introduced into the combustion space through the horizontal row of inlets 18 opening from the channel 13.

inasmuch as there will be some unevenness in the cooling effect by virtue of this r long travel of the air, I start the next lowest 80 compartment or channel 14 on the right hand side of Fig. 3, the entering air traversing first the side wall 12 then the rear wall 10, then the sidewall 11 and the front wall 9, as indicated by the dotted arrows. In other words, the air flowing through this com partmenttraverses the walls in the opposite direction 'from' that which flows through the compartment 13. lt will be, of course, un-

18 in the front wall for delivering the preheated air into the combustion space.

The compartment 15 AVhas thefair'traveling therethrough in the 'same direction as the case with the compartment 13. If additional compartments be added the flow would bel alternately reversed, as just described. By alternately reversing the flow of air through the successive compartments, a more uniform cooling effect is obtained so that 100 vthe liability of difficulty from uneven eX- pansion' and contraction is materially decreased, While at the same time the air will absorb heat -to the greatest'possible degree thereby enhancing the'eliiciency to the great- 105 est-possible extent. Eachcompartment being .under individual control by the respective dampers 16, any desired regulation may be obtained.

' It will be noted that a cooling screen of ,110

" suitably spacedA tubes 19 is located in the lower portion of the combustion space, such screen being connected into the circulation-of the boiler by downcomersQO and upcomers 2l.' o The screen has several functions, one of which is to cool the precipitating refuse particles passing therethrough to the point of deposit from out of the fuel and flame stream, -to a point below the slagging temperature, so that the deposit. will remain read-ily removable. It will be noted that the headers 2 2 and 23 are located Within the kfront and -rear Walls respectively, and these,

together with the tubes 19 serve to cool the lower portion of the walls surrounding the combustion space. In this connection, the

' tubeisl9 willperform a large amount of the ments to admit more air than the other inf work performed by the boiler by, virtue of their being subjected to radiant heat, by reason o f which they abstract large quantities of heat.

Novel effects are also produced on the combustion itselftover and above that incident to the supplying of preheated air. VVhilenormally there might be a tendency for the inlets nearest the blind end of thevcompartf lets, the 'swirling of the. air produced at the corner of each compartment at the juncture of the respective side Wall and front wall has a tendency to cause more air to flow 'through the end 'inlets farthest removedfrom the blind end of the compartments than would otherwise be the case, and in consequence of this there 1s a substantial uniformity-of delivery through the various inlets. If, ho wever,rowing to certain operating conditions, therev should be nonuniform `.flow through a ,row of inlets conditions will be balancediby the'fact that, 'in the succes sive compartments, the flow is reversed so that, considered as a whole, practically the l lsigned my name.

same conditions will be' maintained over the jacent opposite vertical edges of one wall of the chamber and the blind end of each channel being adjacent-,the air inlet for that channel, whereby the air traverses adjacent channels in opposite directions, and means for ad.- mitting the fuel.

2. A combustion chamber for burning fuel in finely divided form in suspension,'having an outlet in an upper part, and means. for admitting fuel in a downward direction at onel side of the combustion chamber so that thefuel and flame stream reverts in U-form, the walls of said chamber being .provided -with vertically spaced channels extending horizontally 'substantially around the chamber, each channelbeing blind at one end,

with air outletsi-nto the combustion space in the regionof the blind end and having an -air .inlet ,at the other end, the air inlets for adjacent channels being located adjacent opposite vertical edges of one wall of the chamber and ,ther blind end Vof each channel being adjacent the air `inlet for that channels in opposite directions.

In testimony channel, whereby the air traverses adjace1it l HENRY KREIsiNGEa whereof, Ihave Ahereunto 

